Answer:
Conformation
Step-by-step explanation:
Conformation refers to "any of the spatial arrangements which the atoms in a molecule may adopt and freely convert between, especially by rotation about individual single bonds"(Oxford dictionary).
Carbon-Carbon single bonds are known to undergo rotations about its axis. These rotations leads to various conformations. The energy difference between conformations may be low or high depending on the structure of the molecule. The difference in energy between conformations determines a molecules's preferred conformation.